For those of us fortunate enough to have the privilege, late December and early January bring two things: new toys and a bit of vacation time. That makes it a great time to tinker with little tech projects, things that are inessential and maybe a bit time-consuming but fun enough and useful enough to be worth doing.

One of my projects was to experiment with classic console emulators on the new Apple TV. There aren’t many of them yet, and installation takes a little work (Apple doesn’t allow add-your-own-ROM emulators in the App Store), but new capabilities introduced in iOS 9 and the iOS-based tvOS make it possible to install them.

Emulation and the Apple TVx

Right now there are two notable emulation projects targeting tvOS. One is a distant relative of the MAME arcade emulator, though it doesn’t seem as though it’s being maintained. Another, Provenance, is the one we’ll be spending the most time with. It’s a multi-system emulator that supports most major 8- and 16-bit consoles, including the NES, SNES, Sega Master System, Sega Genesis, Sega CD, Game Boy, and Game Boy Advance.

You find yourself traveling abroad or in a strange city and need to work out where you are and what’s around you. What do we all do? It’s a familiar process. You take out your smartphone and open multiple apps: Foursquare, Yelp, Maps, Wikipedia, Trip Advisor, etc. The list goes on. After perusing multiple channels of information, you’ve basically lost plenty of time at… Read More

India is Uber’s second largest market worldwide behind only the U.S., and the company is today bolstering its position in the Asian country after agreeing to an alliance with media firm Times Internet. One component of that deal is an undisclosed investment from Times Internet. Read More

If the coin is fair, there is a simple procedure for choosing between 3 items randomly. The group can flip the coin two times, and that will produce 4 events with equal probability: HH, HT, TH, and TT. Let the first three outcomes correspond to each of the three choices. If the fourth event happens (TT), then disregard it and repeat with two more flips.

If heads occurs more frequently than tails, it will no longer be true that HH and HT occur with the same probability. So how can we choose between 3 items in this case?

It seems like we are stuck, but we can use a trick. Let’s first see how we can choose between 2 items. In other words, let’s make a “fair toss” from this unfair coin.

The procedure is this. Flip the coin 2 times. Let HT denote one choice and TH denote the other. If the flip is HH or TT, then disregard and repeat with two flips again.

We can prove this results in creating two events that happen with equal chance. To see why, let’s say that H occurs with probability p and T with probability 1 – p. When we flip the coin twice, we have:

HT occurs with p(1 – p)
TH occurs with (1 – p)p

We’ve created two events that happen with equal chance, even though the coin itself is biased. The trick was making sure to only consider outcomes where the number of H’s equals the number of T’s.

How can we generalize this for choosing between 3 items?

What we have to do is flip the coin 4 times. Now we disregard the ouctcome if the number of H’s and T’s is not equal. We are left with 6 choices in which there are 2 H’s and 2 T’s. We can label these as follows:

This procedure will result in each of the three restaurants being chosen with equal chance.

(Obviously this is just one way to label the outcomes with choices. Any method that assigns 2 of the equally likely events to each of the 3 choices will be valid.)

Generalizing to n

Based on this logic we can make random choices between n choices using a coin. (This is not the most efficient way to do it, but it’s easy to understand which is important so everyone can agree the procedure is fair!)

If the coin is fair: flip the coin k times with 2k ≥ n > 2k-1. Label n of the equally outcomes with each of the choices 1, 2, …, n. For any other outcome flip the coin again until it results in one of the labeled choices.

If the coin is not fair: We need to flip the coin so there are at least n outcomes where the number of heads is equal to the number of tails. That means we should flip the coin 2k times such that 2k choose k ≥ n. Label n of the equally outcomes with each of the choices 1, 2, …, n. (We can make this slightly more efficient. We can actually accept jn of the outcomes by dividing the outcomes into n groups of j outcomes each. Recall that in the case of n = 3, we has 6= 2*3 outcomes that were divided into 3 groups where each choice got 2 outcomes). For any other outcome flip the coin again until it results in one of the labeled choices.

Watching GoPro footage makes it clear that there is basically nothing cooler than first-person action sport shots. And for those who are spending the day at the skate park, one Kickstarter project is hoping to take that genre of filming to the next level.

STABiLGO is a handheld, motorized GoPro stabilizer that keeps the camera level and steady as you turn down a half-pipe or mountain. Creators Michael Boczon and Christine Reilly have raised $33,885 of their $100K goal so far with 12 days left.

If you’re wondering how this product didn’t exist already — produced by someone like GoPro or one of its die-hard fans, for instance — don’t ask Boczon. He doesn’t know either. A technical producer and video editor at MTV, he said others had advanced directly to creating aerial rigs and somehow bypassed handheld stabilizers. But Boczon and Reilly have clearly caught a technology wave that others are riding, too. The day after they had been rewinding motors for the STABiLGO, a pre-made motor became available for purchase online.

After playing catch-up with the development of the individual components, STABiLGO seems to have broken ahead of the pack. After STABiLGO went up on Kickstarter, six different groups reached out to say that Boczon had beaten them to the punch by only a few weeks.

The aim is to move STABiLGO into retail production in China, which Boczon said he intends to do with or without the Kickstarter money. The prototype costs about $450 in parts to produce, and Boczon said they would likely set the retail price between $600-$700.

“In the end, our goal was to use it when we go snowboarding,” he said. “Come this season, I will have my unit.”